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A certain particle ‘X’ has 17 protons, 18 electrons and 20 neutrons. What is the mass number of X? - Chemistry

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Question

A certain particle ‘X’ has 17 protons, 18 electrons and 20 neutrons.

What is the mass number of X?

Numerical
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Solution

Given: Protons = 17

Neutrons = 20

Formula: Mass Number = Number of Protons + Number of Neutrons

= 17 + 20

= 37

So, the mass number of particle X is 37.

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Chapter 4: Atoms, Molecules and Radicals - Additional questions

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Selina Concise Chemistry [English] Class 7 ICSE
Chapter 4 Atoms, Molecules and Radicals
Additional questions | Q 22.2

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